1. Field of the Invention
The present invention relates to a surface-emission unit used in a backlight unit for a liquid crystal display device or a lighting equipment, and composed of a light-emission element module having a light-emission element, and a method for producing the same.
2. Description of the Related Art
Since a liquid crystal display device such as a liquid crystal television or a liquid crystal monitor does not emit light from the liquid crystal itself, it needs a light source to emit light from a back surface for display. As the light source, a solid-state light-emission element such as a fluorescent tube or an LED (Light Emitting Diode) is used, and in either case, it needs to be designed such that uniform light can be obtained in a display area.
FIG. 14 shows a conventionally used configuration of a substrate on which a light-emission element is mounted (light-emission element module). As disclosed in Japanese Unexamined Patent Publication No. 2008-305940, an LED 5 is directly provided on a substrate 11, and the substrate 11 and the LED 5 are connected by a wire 8, and a cap 41 provided by integrally molding a lens part 41a and a reflector part 41b is bonded with a bonding resin 32 in order to protect the LED 5 and the wire 8 on the substrate, and a transparent sealing resin 42 is applied into the cap 41 and cured by heat, whereby the module is completed.
However, in the case of the above conventional technique, the cap is fixed to the substrate 11 with the bonding resin 32 over a whole bottom surface of the cap 41. At this time, in a case where the bonding resin is liquid, since it is necessary to apply the bonding resin 32 to the bottom surface of the cap 41 or a region of the substrate 11 corresponding to the shape of the bottom surface of the cap, it takes time to apply the resin. In addition, an amount of needed bonding resin increases. In a case of a sheet-shaped or tape-shaped bonding material also, it needs a relatively large bonding area. Therefore, it is thought that without applying the resin to the whole bottom surface of the cap 41, the resin is only applied to a part of bottom surface of the cap 41 or the region on the substrate 11 corresponding to the shape of the bottom surface of the cap, in the shape of a dot.
However, in this case, a shadow is formed when the bonding resin shields the light from the light-emission element. The shadows overlap with each other and are emphasized depending on the way of arranging the light-emission elements, so that linear irregularity in brightness is generated in the surface-emission unit used in the liquid crystal television, liquid crystal monitor, or surface emission type lighting equipment.